Evaluating of some Herbicides to Control Bermudagrass (Cynodon dactylon) and Field Bindweed (Convolvulus arvensis) in Established Alfalfa (Medicago sativa)

In order to evaluate the effect of some herbicides for weed control in established alfalfa، an experiment was conducted in a randomized complete blocks design with 4 replications in the Agricultural Research Center of Jiroft، for two years from 2009 to 2011. Treatments included Pursuit (imazethapyr SL 10%) at 0. 4، 0. 6، 0. 8 and 1 Lit/ha plus cytogate at 1 Lit/ha، plus Focus (cycloxydim EC 10%) at 2 Lit/ha، Stomp (pendimethalin EC 33%) at 2. 5 and 3 Lit/ha، Bazagran (bentazon SL 48%) at 3 L/ha plus focus at 2 Lit/ha، Senkor (metribuzin WP 70%) at 1 kg/ha، Butress (2،4،DB 42. 3 % EC) at 2، 2. 5، 3، 3. 5 li/ha and weed- free as a check. The effect of herbicides on alfalfa biomass and weed biomass and density was studied from 3 harvests. Herbicides had significant effect on the density and biomass of bermudagrass (Cynodon dactylon) and field bindweed (Convolvulus arvensis). Herbicide cycloxydim، at 2 L/ha، was best to control bermudagrass، reducing density by 47-64% and dry weight by 47-62%. The best treatment to control field bindweed was 2،4-DB at 3. 5 L/ha، reducing density by 38-42% and dry weight by 36-39%. The highest alfalfa yield was obtained with imazethapyr at 0. 8 and 1 L/ha plus cytogate at 1 Lit/ha، plus cycloxydim at 2 Lit/ha.